The extrinsic pathway of blood coagulation is initiated when FVIIa circulating in plasma binds to the integral-membrane protein, tissue factor (TF). The role of TF in blood coagulation has been extensively studied (Camerer, E., A. B. et al. Thromb. Res. 81: 1-41, (1996)). The involvement of FVIIa as a proteolytic enzyme in the blood coagulation cascade is believed to be confined to the extracellular leaflet of TF expressing cells. An intracellular activity of FVIIa was first implied when the sequence of TF showed homology to the cytokine/interferon- or heamatopoietic receptor superfamily (Bassoon, J. F. Proc. Natl. Acad. Sci. USA 87: 6934-6938, (1990)). The subclass I of the heamotopoietic receptor family includes receptors for growth hormone, prolactin, interleukins 1 to 7, granulocyte- macrophage colony stimulating factors, erythropoitin and thrombopoitin. Subclass II includes TF and receptors for interferon .alpha. and .beta. (Wells, J. A., and De Vos, A. M. Annu. Rev. Biomol. Struct. 22: 329-351, (1993)). The resemblance of TF to this class of receptors was further substantiated with the appearance of the crystal structure (Harlos, K., D. M. A. et al. Nature 370: 662-666, (1994), Mueller, Y. A., M. H. et al. Biochemistry 33: 10864-10870 (1994)). Characteristic of this class of cytokine receptors that includes receptors for interferon .beta. and .gamma. and IL-10 (Mott, H. R. and Campbell, I. D. Curr. Opin. Struct. Biol. 5: 114-121, (1995)) is that their activation lead to rapid tyrosine phosphorylation of the receptors themselves, as well as a subset of intracellular proteins. Within minutes after the initial tyrosine phosphorylation an array of mitogen-activated (Ser/Thr) kinases (MAPK) is activated (Whitmarsh, A. J. and Davis, R. J. J. Mol. Med. 74: 589-607, (1996)). These kinases are arranged in several parallel signalling pathways (David, M. et al. Science 269, 1721 (1996); Current opin. immunol. 8, 402-11 (1996)). Thorough studies of the putative intracellular signalling capacity of FVIIa have shown that it induce mobilisation of intracellular free calcium (Ca.sup.2+) in the human bladder carcinoma cell line, J82, which constitutively express TF and in umbelical vein endothelial cells which were pre-treated with interleukin-1 to express TF (Rottingen, J.-A. et al. J. Biol. Chem. 270: 4650-4660, (1995)), but have failed to show any cytokine-like activation of intracellular tyrosine kinases (Camerer, E., et al. J. Biol. Chem. 271: 29034-29042, (1996)). In conclusion FVIIa is believed, in a TF dependent manner, to induce mobilisation of intracellular Ca.sup.2+ through activation of phospholipase C (Camerer, E., et al. J. Biol. Chem. 271: 29034-29042, (1996)). The mechanism by which FVIIa activates phospholipase c is not known, but Camerer et al. specifically ruled out tyrosine kinase activation.